First Aid Embryology

Front 1

gene produced at base of limbs in zone of polarizing activity, involved in patterning along anterior-posterior axis

Back 1

Sonic hedgehog gene

Front 2

necessary for proper organization along dorsal-ventral axis, associated with thickened ectoderm at distal end of each developing limb

Back 2

Wnt-7-gene

Front 3

involved in segmental organization of embryo in craniocaudal direction

Back 3

homeobox gene

Front 4

stimulates mitosis of underlying mesoderm, provides lengthening of limbs

Back 4

FGF gene

Front 5

alar plate

Back 5

associated with sensory (dorsal)

Front 6

basal plate

Back 6

associated with motor (ventral)

Front 7

notochord becomes what in adults

Back 7

nucleus pulposus of the intervertebral disk

Front 8

benign rathke's pouch tumor

Back 8

craniopharyngioma

Front 9

came from rathke's pouch

Back 9

adenohypophysis - surface ectoderm

Front 10

twinning: before day 3, between day 3 and 8, after day 8

Back 10

before day 3 - dichorionic, diamniotic placenta
between - monochorionic, diamniotic placenta
after day 8 - monochorionic, monoamniotic placenta

Front 11

fetal part of placenta that contributes to outer layer of chorionic villi and secretes hCG

Back 11

syncytiotrophoblast

Front 12

umbilical arteries and veins are derived from what

Back 12

allantois

Front 13

single umbilical artery is associated with what

Back 13

congenital and chromosomal anomalies

Front 14

during 3rd week, the allantois becomes what

Back 14

urachus - duct between the bladder and yold sac

Front 15

two problems associated with failure of urachus to obliterate

Back 15

urine discharge from umbilicus
outpouching of bladder - vesicourachal diverticulum

Front 16

connects yolk sac to midgut lumen

Back 16

vitelline duct

Front 17

failure of closure of vitelline duct

Back 17

vitelline fistula - meconium (stool) discharge from umbilicus

Front 18

meckel's diverticulum

Back 18

partial closure of vitelline duct, with patent portion attached to ileum

Front 19

gives rise to ascending aorta and pulmonary trunk

Back 19

truncus arteriosus

Front 20

gives rise to RV and outflow tract of Left and Right ventricle

Back 20

bulbus cordis

Front 21

contribution to form the membranous IV septum

Back 21

aorticopulmonary septum fuses with muscular ventricular septum
endocardial cushions contribute to atrial separation and membranous IV septum

Front 22

causes initial left-to-right shunting, eventually becomes right-to-left due to eisenmenger complex

Back 22

membranous septal defect (VSD)

Front 23

contains the foramen ovale

Back 23

septum secundum

Front 24

forms valve of foramen ovale

Back 24

remaining portion of septum primum

Front 25

fetal erythrypoiesis locations at different weeks

Back 25

yolk sac 3 - 8
liver 6 - 30
spleen 9 - 28
bone marrow 28 onward

Front 26

bypasses hepatic circulation in embryo allowing blood to enter straight to IVC from umbilical vein

Back 26

ductus venosus

Front 27

bypasses lung circulation in embryo

Back 27

foramen ovale

Front 28

diverts blood from pulmonary artery to aorta in the embryo

Back 28

ductus arteriosus

Front 29

what happens when infants take first breath

Back 29

decreases resistance in pulmonary vasculature leading to increased blood flow and increased left atrial pressure closing the foramen ovale

Front 30

drugs that keep PDA open

Back 30

prostaglandins

Front 31

drug to help close PDA

Back 31

indomethacin

Front 32

associated with elevated a-fetoprotein in amniotic fluid

Back 32

neural tube defect

Front 33

large posterior fossa and absent cerebellar vermis

Back 33

Dandy-walker

Front 34

what does chiari malformation often present with

Back 34

syringomyelia
thoracolumbar myelomeningocele

Front 35

why is polyhydramnios associated with anencephaly

Back 35

no swallowing center in brain

Front 36

enlargement of the central canal of spinal cord
most common site

Back 36

syringomyelia
C8-T1

Front 37

associated with cape-like loss of pain and temperature sensation in upper extremities with presevation of touch sensation

Back 37

syringomyelia

Front 38

associated with proximal part of pulmonary arteries and ductus arteriosus

Back 38

6th aortic arch derivatives

Front 39

associated with aortic arch and proximal part of right subclavian artery

Back 39

4th aortic arch derivatives

Front 40

remnants of 1st, 2nd, and 3rd aortic arch

Back 40

1st - maxillary artery
2nd - stapedial and hyoid arteries
3rd - common carotid

Front 41

what are each of the branchial apparatus parts derived from: clefts, arches, pouches

Back 41

clefts - ectoderm
arches - mesoderm
pouches - endoderm

Front 42

branchial cleft cysts is derived from which branchial cleft

Back 42

2nd branchial cleft (persistant cervical sinus)

Front 43

Treacher Collins syndrome: 1st arch neural crest fails to migrate

Back 43

mandibular hypoplasia
facial abnormalities

Front 44

CNs associated with 1st branchial arch

Back 44

V2 and V3 - chewing

Front 45

CN associated with 2nd branchial arch

Back 45

CN VII - facial expression

Front 46

CN associated with 3rd branchial arch

Back 46

CN IX

Front 47

CN associated with 4-6 arch

Back 47

CN X
4th - superior laryngeal branch (swallowing)
6th - recurrent laryngeal branch (speaking)

Front 48

associated with persistence of 3rd branchial cleft and pouch

Back 48

fistula between tonsillar area
cleft in lateral neck

Front 49

develops into inferior parathyroids and thymus

Back 49

3rd branchial pouch

Front 50

develops into super parathyroids

Back 50

4th branchial pouch

Front 51

aberrant development of 3rd and 4th pouches

Back 51

DiGoerge syndrome:
T cell deficiency and hypocalcemia

Front 52

associated with MEN 2A: mutation of RET gene (neural crest cells)

Back 52

pheochromocytoma - adrenal medulla
parathryoid tumor - 3rd/4th pharyngeal pouch
medullary thryoid cancer - 4th/5th pharyngeal pouches

Front 53

forms anterior 2/3 of tongue

Back 53

1st branchial arch

Front 54

forms posterior 1/3 of tongue

Back 54

3rd and 4th branchial arches

Front 55

normal remnant of thryoglossal duct

Back 55

foramen cecum

Front 56

how to distinguish between thyroglossal duct cyst and branchial cleft cyst

Back 56

thyroglossal duct cyst is midline neck vs. lateral neck
thyroglossal also moves with swallowing

Front 57

foregut
midgut
hindgut

Back 57

foregut - pharynx to duodenum
midgut - duodenum to transverse colon
hindgut - distal transverse colon to rectum

Front 58

persistence of herniation of abdominal contents into umbilical cord, covered by peritoneum

Back 58

omphalocele

Front 59

extrusion of abdominal contents through abdominal folds, not covered by peritoneum

Back 59

gastroschisis

Front 60

associated with duodenal atresia

Back 60

trisomy 21

Front 61

when does the midgut herniate through umbilical ring

Back 61

6th week

Front 62

when deos the midgut return to abdominal cavity and rotate around superior mesenteric artery (SMA)

Back 62

10th week

Front 63

most common TE fistula

Back 63

blind upper esophagus with lower esophagus connected to trachea

Front 64

findings associated with most common TE fistula

Back 64

air bubble in stomach
polyhydramnios
failure to pass NG tube into stomach
penumonitis

Front 65

associated with nonbilious projectile vomiting at about 2 weeks of age

Back 65

congenital pyloric stenosis

Front 66

annular pancreas

Back 66

when ventral pancreatic bud encircles 2nd part of duodenum and can cause duodenal narrowing

Front 67

functions as kidney for 1st trimester - later contributes to male genital system

Back 67

mesonephros

Front 68

derived from caudal end of mesonephros - induces differentiation of metanephros to form glomeruli and renal tubules

Back 68

uteric bud

Front 69

most common site of kidney obstruction in fetus leading to hydronephrosis

Back 69

uteropelvic junction (ureter and renal pelvis)

Front 70

Potter's syndrome

Back 70

results from oligohydramnios due to bilateral renal agenesis:
limb deformities, facial deformities, pulmonary hypoplasia

Front 71

which artery traps the horseshoe kidney from ascention

Back 71

inferior mesenteric artery

Front 72

degenerates in normal female embryo

Back 72

mesenephric duct - paramesenephric duct develops

Front 73

gene found on Y chromosome that produces testis-determining factor

Back 73

SRY gene

Front 74

sertolid cells secrete what to suppress the development of paramesenphric ducts

Back 74

mullerian inhibiting factor

Front 75

default embryo development

Back 75

female - mesonephric duct degeneration with paramesonephric duct development

Front 76

stimulates development of mesonephric ducts

Back 76

increased androgens from Leydig cells

Front 77

results from incomplete fusion of paramesonephric ducts

Back 77

bicornuate uterus

Front 78

abnormal opening of penile urethra on inferior (ventral) side of penis

Back 78

hypospadius

Front 79

abnormal opening of penile urethra on superior (dorsal) side of penis

Back 79

epispadius

Front 80

associated with extrophy of the bladder

Back 80

epispadius

Front 81

female and male remenants of gabernaculum

Back 81

female - ovarian and found ligament of uterus
male - anchors testes within scrotum

Front 82

forms the tunica vaginalis

Back 82

processus vaginalis (evagination of peritoneum)